This invention relates to apparatuses and methods for monitoring physiological conditions and, in particular, devices and methods suited for monitoring a plurality of ambulatory patients simultaneously from a remote location.
Physiological conditions of patients, such as blood pressure and heart rate, have been conventionally monitored using one monitor per patient. The equipment is linked to the patient and thereby restricts his or her movement. The monitoring is usually done in the presence of healthcare professional and the procedure itself can affect the physiological conditions (also known as vital signs) being monitored.
There has been an increased need to provide an apparatus and method for monitoring a plurality of patients simultaneously and automatically without restricting movement of the patients concerned and without requiring the presence of healthcare providers. A number of automated, ambulatory systems have been developed for blood pressure measurement for example. However, typically the patient must report to a medical office or other specified location in order to download the information collected. Real time or near real time information about an ambulatory patient is not conventionally available. Such a system would be desirable and would reduce the costs of monitoring a plurality of patients.
U.S. Pat. No. 4,958,645 to Cadell discloses a medical radio telemetry system which includes a plurality of telemeters with one telemeter located on each patient. The patent also discloses a method of switching antennas to obtain the best signal. However there is no provision for automatically identifying and displaying the different signs of a plurality of patients separately on a remote computer. Furthermore, utilizing a plurality of antennas may not increase the reliability of the system when both antennas encounter the same random noise simultaneously.
U.S. Pat. No. 5,482,049 to Addiss et al. discloses a method for labelling various vital signs of a patient. However the system is not well adapted for simultaneous use on a plurality of patients.
U.S. Pat. No. 5,157,604 to Axford et al. discloses a method for monitoring heart rate for plural persons using radio telemetry. The system however uses pre-determined time sequences. This means time is wasted in sending data from patients when monitoring is not required. A preferable system would transmit data on demand.
U.S. Pat. No. 5,417,222 to Dempsey et al. discloses a method and apparatus for performing patient monitoring which interfaces a telemetry monitor with a standard portable computer. The system however does not have adequate provision for separately monitoring a plurality of patients.
Accordingly, it is an object of the invention to provide an improved telemetry monitoring system which can simultaneously display physiological conditions of a plurality of patients on a real time or near real time basis.
It is also an object of the invention to provide an improved telemetry monitoring system which is compatible with standard desktop computers commonly used in medical facilities.
It is a further object of the invention to provide an improved telemetry monitoring system which is reliable and relatively error-free.
It is a still further object of the invention to provide an improved telemetry monitoring system which is efficient and, in particular, transmits information at a rate or at times dictated by demand.